The present invention relates to an arrangement in a throttle-controlled internal combustion engine equipped with a supercharger in the form of an air compressor which comprises helical rotors (male and female rotors) located in a compression chamber and which is connected via a transmission arrangement to the crankshaft of the vehicle engine.
Known arrangements of this kind suffer the drawback of poor efficiency when the compressor is working at partial load. Another drawback encountered with such arrangements is that difficulties are encountered with regard to the mutual co-action between the supercharger and the fuel supply system. Furthermore, when passing from partial load to full load, there is a delay before full charging pressure is reached.